Well digging apparatus



July 19, 1932. y F, N STOVER 1,868,400

WELL DIGGING APPARATUS Filed Sept. 17, 1929 2 Sheets-Sheet` l July 19, 1932. F. N. s'rovER WELL DIGGING APPARATUS Filed Sept. 17. 1929 2 Sheets-Sheet 2 Patented July 19, 1932 1,868,400

UNITED STATES PATENT OFFICE FRED N. STOVER, F NEW KATAMORAS, OHIO WELL DIGGING APPARATUS Application led September 17, 1929. Serial No. 393,279.

The invention is directed to a method of pressure into the working plane of and diand apparatus for digging wells, particurectly beneath the hammer to assist the hamlarly oil wells, through percussive or hammer in its excavating function and also assist mering action. the hammer in its return movement follow- In driving wells through percussive or ing each hammer blow. hammering action, it is extremely diilicult A further object of the invention is the if not impossible to eliminate from the plane provision of means whereby the pipelines deof action of the hammer the cuttings incident ning the water and air columns may be relato the hammering action. This is particutively associated in a manner to permit their larl true as in the use of a hammer there convenient withdrawal, with the sections of is little if any clearance, and in order that the air column line sealed at their juncture the hammer may proceed with an effective against leakage and maintained under sealresult, it is absolutel necessary that the cuting cooperation by manually adjustable tings bey cleared. t is, therefore, an immeans conveniently accessible at the upper portant object of the present invention to endof the well. 00 provide for the effective clearing of these The invention is illustrated in the accomcuttings and in the method described this panying drawings, in which: clearing is effected by the introduction of Figure l is a view in elevation of the imwater under pressure supplemented by the proved well digging assembly.

10 intermingling therewith of air under pres- Figure 2 is an enlarged sectional view, o5

sure. Again, when soft material is enpartly in elevation, of the hammer barrel and countered, particularly where the hammer is the hammer. acting to somel extent against the weight of Figure 3 is an enlarged vertical sectional the column of water used to float the excaview of the casing immediately above the vated material to the surface, there is such a hammer barrel. 7o gripping of the hammer as to materially re- Figure 4 is a section on line 4 4 of duce it not completely interrupt the ham- Figure 2. mering action. Figure 5 is a vertical sectional view show- 'l`he improved method broadly directed to ing the means for connecting the sections of overcoming these difliculties is the utilization the air tube against leakage. of a portion of the air directed under pres- Figure 6 is a bottom plan view of the hamsure for the operation of the hammer as a mer barrel. medium for aerating and thereby reducing Figure 7 is a vertical sectional view shown the weight of the water column to not only ing the means for connecting the air supply J assist in the flotative effect of such column tube and the air tubes and for exerting pres- 8o but to use the lighter medium thus created sure on the air tubes to seal the juncture beto assist in the return movement of the tween the air tube sections. hammer. The improved well digging assembly infurther object of the invention is the cludes a tubular well casing 1 made up of a 0 utilization of the aerated water under presplurality of sections connected by cou lings 85 sure as a means for inducing a slight rotative 2 in order that the casing may bead ed to movement 'of the hammer for effective excafrom time to time as the digging operation vation. proceeds. The lower section of the casing, r A further object is the provision of means indicated at 3, is in the form of a barrel for for directingacolumn of aerated water underv the reception of the hammer parts. These are primarily conventional, except inthe particulars hereinafter specifically referred to, and may he briefly indicated as Valve lucchanism 4, piston 5, anvil 6, bit piston 7 and tool 8, the bit piston of course being designed to receive di'erent types of bits or tools. The bit piston is circumferentially reduced above its connection with the bit, as at 9, and packing 10 is introduced between the portion 9 of the bit piston and the valve.

That portion'of the hammer barrel immediately above the upper limit position of the valve is formed with a centralvertical passage 11 providing a pressure supply passage for the valve and with a plurality of outer vertically extending passages 12 providing exhaust passages for the valve. The upper end of the passage 11 terminates in a conical enlargement 13 to receive the lower end of the air pipe 14 through which air under pressure is delivered to the valve for the operation of the hammer. The casing section concentric with land above the enlargement 13 is formed with a further conical depression or opening 15, the interior conical wall of which is designed to sealingly and removably receive and cooperate with the lower end of the water pipe 16, which water pipe is in spaced concentric relation with the air pipe 14. The water pipe is made up in sections and the outer surface of the lower end of the lowermost section is beveled, as at 17, in correspondence with the conical wall of the opening 15, so that the water pipe as a whole may, by suitable driving action, be accurately centered and sealed with respect to this wall. The air pipe 14 is also made up in sections and the lowermost section has its lower end beveled in accordance with the inclination of the wall of the enlargement 13, so that under suitable driving action a sealing juncture at this point may be provided.

The respective sections of the air pipe are arranged in sealing juncture with each other to prevent leakage through the means indicated more particularly in Figure 5. As here shown, the respective sections of the water pipe 16 are connected by threaded couplings 18, each provided with an inwardly extending angular ange 19 formed with a series of vertical holes 20 to permit the uninterrupted flow of water, or such ilange may be merely in the form of diametrically opposed projections. Each section of air pipe 14 is formed at its upper end with anJ integral or otherwise secured enlargement 21 having a diameter less than thev interior diameter of the coupling 18 with the enlargement including an upstanding wall 22, the interior diameter of which is greater than that of an p which is slightly less than the interior diameter of the wall 22.

In assembling the air tube sections, compressible acking 24 is arranged in the space between t e lower end of a tube section and the wall 22 of the enlargement of the next lower section, the packing underlying the flange 23. Means are provided, as will later appear, at the upper end of the well for exerting an endwise pressure on the connected air tube sections, thus effectively compressing and `distending the packing 24 to completely seal the juncture between the sections of the air tube, and permitting their separation when withdrawal is contemplated by a simple endwise movement.

As previously stated, air under pressure is delivered through the air tube 14 'for operating the air hammer and water under more or less pressure is delivered into the Water pipe 16 for the ilotation of the material excavated by the hammer to the surface of the well.

The method of the present invention aims to take advantage of the air under pressure for the purpose of aerating the water delivered to the bottom of the well in order to increase the buoyant effect of the water and to utilize it in such more l`or less areated condition as a means of assisting the displacement of the hammer following each blow both vertically and in rotary movement.

The delivery 'of the water through the water pipe 16 to the bottom of the well is provided for through a plurality of vertically arranged-channels 25 formed in the hammer barrel 3, these channels communicating at their upper ends through inwardly deflected ducts 26 with the lower end of the opening 15 within the plane of the water pipe 16. The upper ends of these ducts are provided with valves 27 which close against a return or upward movement of the water. The air pressure `'channel 11 leading to the hammer valve is in open communication with the ducts 26, below the valves therein, through passages 28, preferably in the form of tapered jet passages to increase the velocity of the air delivered therethrough, these passages 28 being also provided with non-return valves 29.

Thus, there is a free delivery of water from the water pipe to that portion of the well being operated on by the hammer, and a portion of the air under pressure is deliverd to this water column or columns, so that the water is thoroughly mixed with the air before it reaches the bit or tool.

The bit and bit piston are formed with a central water passage 30 which, within the piston, has 'a lateral section 31 communicating with an annular chamber 32 in the peripheral surface of the bit piston below the packing 10. The wall of the barrel 3 is formed in line with the chamber 32 with transverse passages 33 communicating at their inner ends with the chamber 32 and at their outer ends with the ducts 26. A ortion of the aerated water is thus continuously delivered through the bit and directly onto and in contact with the surface being worked on.

Thel lower end of the hammer barrel terminates, of course, above the bit in order to permit the necessary reciprocating movement of the bit, and the channels 25, of which there are preferably four, open at equally spaced points through the lower end of the barrel. The upper shoulder of the bit, indicated at 34, underlies the lower end of the barrel and the bit is formed with vertically extending channels 35 which terminate at their lower ends at the bottom of the bit in slightly spaced relation with the central channel 30 and at their upper ends in a plane in vertical alignment with the plane of the lower ends of the channels 25. The channels 35 are preferably three in number and their upper ends are materially enlarged, with the enlargements of downwardly convergent conical form.

As the aerated water under pressure is delivered in a series of streams from the outlet ends of the channels 25, one or more of such streams will engage with one or more of the conical ends of the channels 35, and the force of the water stream will tend to center or align a particular channel 35 with a particular channel 25. Y

At the upper end of the well, water is delivered into the water pipe 16 from a suitable source of water under pressure through a conduit 36 connected with the upper section of water pipe by a union 37. Air is delivered to the air pipe 14 from a suitable source of air under pressure through a pipe line 38. The terminal of the air line 38 is connected to the upper section of the air pipe 14 by a collar 39, housed in an extension 40 of the coupling 37. A packing 41 overlies the collar 39, the packing also seating in an enlarged recess in the extension 40. A gland 42, removably connected to the terminal of the pipe line 38, rests upon the packing 41 and is vertically adjustable with respect to the coupling enlargement 40 through the medium of bolts 43 rising from the coupling enlargement and passing through the gland. Nuts 44 are arranged to engage the bolts to force the gland into sealing relation with the packing 41. Under pressure on the packing and on the collar 39 through this adjustment of the gland, the various packings 24 connecting the respective sections of the air tube within the well are vertically compressed and laterally distended to seal the juncture between the air pipe sections. Thus, the air pipe is rendered a non-leaking continuity by a proper compressive seating of the gland 42.

As previously stated, where the bit or hammer is working in soft semi-'fluid material, there is such a decided grip on the tool by this material as to materially interfere with if not completely interrupt the movement of the tool. The weight of the column of water through which thelibterial with an inherent tendency to check or stop the bit.

As noted from the preceding description, this aerated water, or water highly charged with air under pressure, is delivered around and beneath the bit. The contained air will have the effect of aninherent pressure medium below and around the lower end of the bit which, by the very reason of this pressure, will tend to materially assist the return or upward movement of the bit and prevent its possible choking when operating in materials of a certain character. Furthermore, this air-charged water, through its increased buoyancy, materially reduces the over-all pressure on the bit and on the material being operated on, and not only assists the separated material in reaching the surface of the well in greater volume in a given space of time but relieves the bit of a pressure against which it would otherwise have to operate in its excavating function.

The method fundamentally apparent from the present application is the introduction of a fluid pressure medium, such as air, for the operatlon of the hammer and the further introduction of a fluid pressure medium, such as water, as a flotative medium, and introducing a portion of the air under pressure into the flotative medium to increase the flotative function and more particularly for the creation of a reactive pressure on the bit to prevent choking of the latter in use.

The broad feature of the present method that is the aeration of water, is also particularly useful in connection with well digging operations where, from the known geological formation and the depth at which the hammer is working, it is known that the hammer is operating in a pay formation, or in a stratum desired to be investigated. Under these circumstances, the well digging apparatus described is pulled from the well and the hammer barrel and hammer parts, together with a sufficient length of casing 3 to maintain desired weight on the hammer, is lowered into the well, as for example by a wire-line, after b-ailing the well. A sufficient length of air hose or other conduit is'lowered into the well to communicate with the vertical passage 11 for supplying air pres sure to the hammer and permitting the necessary. portion of the air under pressure to bypass into the channels 25. Water 1s then poured into the well for an appropriate height but there is no further water delivered to the well and no delivery of water under pressure to the well.

As the hammer proceeds with its excavating operation, the air delivered through the hammer and through the channels 25 maintains the water in a constant state of agita.

tion with the internal pressure thereof directed more or less upwardly due to the tendency of the air to rise through the body of water and escape. This agitation, in addition to having all the functions previously ascribed thereto in the direct digglng of the well, has the additional function of clearing away the mud, sand and other material surrounding the hammer and causing it to move upwardly in the overlying body ,of water.

This clears the hammer for effective operation and permits a digging through the pay formation in a very inexpensive and labor and time saving manner. When the digging has proceeded to the desired or contemplated degree, the hammer with the connected clasing parts and air tube is ready and conveniently withdrawn from the well and the well bailed in the usual manner to determine the character of the development.

Here, as in the specifically described well digging operation before referred to, the aeration of the water is a material factor in insuring the flotation of the se arated materi al from around the hammer, or under the tendency of the air to rise in the overlying body of water, there is a continual upward pressure in this body of water which will carry the mud and sand upwardly and maintain it in suspension throughout the digging operation or until such accumulation has practically absorbed the quantity of water provided. This particular method step is regarded as an important detail of the present invention and flows directly from the salient and important features of the initial well digging operation previously described and is to be considered within the purview of the claims forming part of and defining the novel features of this invention.

What is claimed to be new is:

1. A method of excavating oil wells and the like wherein the excavation is carried out through an air-driven tool, consisting in delivering air under pressure for the operation of the tool, delivering water under pressure for the flotation of the separated material, diverting a portion of the air under pressure for mixing with the water, and thereafter delivering the combined air and water mixture to a position beneath the tool.

2. A method for excavating oil wells and the like wherein the excavation is carried out through an air-driven tool, consisting in delivering air under pressure into the Well for the operation of the tool, delivering water under pressure into the well for the flotation of the separated material, forcing a portion of the air under pressure into the water, and delivering the aerated water through the tool and to a point below -the tool.

3. A well drilling assembly including an air hammer, means for delivering air under pressure to said hammer, means for delivering water under pressure to the bottom of the well, and means for delivering a portion of the air under pressure to the water column above the bottom of the well.

4. A well drilling assembly including an air hammer, means for delivering air under pressure to the hammer, means for delivering water under pressure to the well, said means including a series of ducts terminating immediately above the tool of the hammer, means for by-passing a portion of the air under pressure into the water prior to the passage ofthe water through said ducts, the tool of the hammer formed with a central passage opening through the lower end of the tool, and means for delivering a portion of the aerated water under pressure through said passage in the operation of the hammer.

5. A well drilling assembly including an air hammer, a casing for supporting said air hammer, an air pipe for delivering air under pressure to the hammer, a water pipe for deliverin g water under pressure to the bottom of the Wellin the vicinity of the hammer, said water pipe surrounding the air pipe, and means for by-passing a portion of the air under pressure -from the air pipe into the body of water.

6. A well drilling assembly including an air hammer, means for delivering air under pressure to the hammer, and means for delivering a combination vof air under pressure and water under pressure to the bottom of the well and directly beneath the hammer.

7 A well drilling assembly including an air hammer barrel, a casing connected to and supporting said barrel within the well, an air hammer and cooperating parts arranged within the barrel, air inlet and exhaust ports for the hammer formed in the casing, water channels formed in the barrel beyond the air hammer parts and opening through the bottom of the barrel, means for delivering air under pressure to the air inlet, means for delivering water under pressure to the water channels, and means for directing a portion of the air under pressure into the water prior to its` passage through said channels.

8. A well drilling assembly including an air hammer barrel, a casing connected to and supporting. said barrel within the well, an air hammer and cooperating parts arranged within the barrel, air inlet and exhaust ports for the hammer formed in the casing, water Channels formed in the barrel beyond the air hammer parts and opening through the bottom of the barrel, means for delivering air under pressure to the air inlet, mea-ns for de- 5 livering Water under pressure to the Water channels, means for directing a portion of the air under pressure into the water prior to its passage through said channels, and means for by-passing a portion of the air and Water under pressure through the center of the hammer.

In testimony whereof I a'ix my signature.

FRED N. STOVER. 

